Generating key for microsoft windows xp

i have a laptop with aspire 1350 make and has been trying to generate the microsoft key and all effort to do this proved abortive.
i have entered the product key given to me by the manufacture which is xxxxxxxxx and it still complains that i have got the wrong key! please forward me with an appropriate key to use so as to log on

Message was edited by: beth.blakely@…